Java enums are handy things. Often used as an effective replacement for simple int constants you can also add methods and fields and make them implement arbitrary interfaces.<\/p>\n\n\n\n
Joshua Bloch has lots of interesting things to say about them in his excellent book, Effective Java<\/em>. Item 34<\/strong> describes a way to emulate extensible enums with interfaces but having an enum implement an interface can also be a simple way to split a large, unwieldy enum into smaller parts.<\/p>\n\n\n\n Consider a simple enum that contains a code and a message:<\/p>\n\n\n\n